xref: /openbmc/linux/Documentation/devicetree/bindings/csky/cpus.txt (revision 3eb66e91a25497065c5322b1268cbc3953642227)
1*19fef6c4SGuo Ren==================
2*19fef6c4SGuo RenC-SKY CPU Bindings
3*19fef6c4SGuo Ren==================
4*19fef6c4SGuo Ren
5*19fef6c4SGuo RenThe device tree allows to describe the layout of CPUs in a system through
6*19fef6c4SGuo Renthe "cpus" node, which in turn contains a number of subnodes (ie "cpu")
7*19fef6c4SGuo Rendefining properties for every cpu.
8*19fef6c4SGuo Ren
9*19fef6c4SGuo RenOnly SMP system need to care about the cpus node and single processor
10*19fef6c4SGuo Renneedn't define cpus node at all.
11*19fef6c4SGuo Ren
12*19fef6c4SGuo Ren=====================================
13*19fef6c4SGuo Rencpus and cpu node bindings definition
14*19fef6c4SGuo Ren=====================================
15*19fef6c4SGuo Ren
16*19fef6c4SGuo Ren- cpus node
17*19fef6c4SGuo Ren
18*19fef6c4SGuo Ren	Description: Container of cpu nodes
19*19fef6c4SGuo Ren
20*19fef6c4SGuo Ren	The node name must be "cpus".
21*19fef6c4SGuo Ren
22*19fef6c4SGuo Ren	A cpus node must define the following properties:
23*19fef6c4SGuo Ren
24*19fef6c4SGuo Ren	- #address-cells
25*19fef6c4SGuo Ren		Usage: required
26*19fef6c4SGuo Ren		Value type: <u32>
27*19fef6c4SGuo Ren		Definition: must be set to 1
28*19fef6c4SGuo Ren	- #size-cells
29*19fef6c4SGuo Ren		Usage: required
30*19fef6c4SGuo Ren		Value type: <u32>
31*19fef6c4SGuo Ren		Definition: must be set to 0
32*19fef6c4SGuo Ren
33*19fef6c4SGuo Ren- cpu node
34*19fef6c4SGuo Ren
35*19fef6c4SGuo Ren	Description: Describes one of SMP cores
36*19fef6c4SGuo Ren
37*19fef6c4SGuo Ren	PROPERTIES
38*19fef6c4SGuo Ren
39*19fef6c4SGuo Ren	- device_type
40*19fef6c4SGuo Ren		Usage: required
41*19fef6c4SGuo Ren		Value type: <string>
42*19fef6c4SGuo Ren		Definition: must be "cpu"
43*19fef6c4SGuo Ren	- reg
44*19fef6c4SGuo Ren		Usage: required
45*19fef6c4SGuo Ren		Value type: <u32>
46*19fef6c4SGuo Ren		Definition: CPU index
47*19fef6c4SGuo Ren	- compatible:
48*19fef6c4SGuo Ren		Usage: required
49*19fef6c4SGuo Ren		Value type: <string>
50*19fef6c4SGuo Ren		Definition: must contain "csky", eg:
51*19fef6c4SGuo Ren			"csky,610"
52*19fef6c4SGuo Ren			"csky,807"
53*19fef6c4SGuo Ren			"csky,810"
54*19fef6c4SGuo Ren			"csky,860"
55*19fef6c4SGuo Ren
56*19fef6c4SGuo RenExample:
57*19fef6c4SGuo Ren--------
58*19fef6c4SGuo Ren
59*19fef6c4SGuo Ren	cpus {
60*19fef6c4SGuo Ren		#address-cells = <1>;
61*19fef6c4SGuo Ren		#size-cells = <0>;
62*19fef6c4SGuo Ren		cpu@0 {
63*19fef6c4SGuo Ren			device_type = "cpu";
64*19fef6c4SGuo Ren			reg = <0>;
65*19fef6c4SGuo Ren			status = "ok";
66*19fef6c4SGuo Ren		};
67*19fef6c4SGuo Ren
68*19fef6c4SGuo Ren		cpu@1 {
69*19fef6c4SGuo Ren			device_type = "cpu";
70*19fef6c4SGuo Ren			reg = <1>;
71*19fef6c4SGuo Ren			status = "ok";
72*19fef6c4SGuo Ren		};
73*19fef6c4SGuo Ren	};
74